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Modern pollen assemblages of the surface lake sediments from the steppe and desert zones of the Tibetan Plateau

Science China Earth Sciences 2021年第3期64卷 425-439页

作者： feng qin Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China

Modern pollen analysis is the basis for revealing the palaeovegetation and palaeoclimate changes from fossil pollen *** studies pertaining to the modern pollen assemblages on the Tibetan Plateau have been conducted,but little attention has been paid to pollen assemblages of surface lake *** this study,modern pollen assemblages of surface lake sediments from 34 lakes in the steppe and desert zones of the Tibetan Plateau are investigated and results indicate that the two vegetation zones are dominated by non-arboreal pollen taxa and show distinctive *** pollen assemblages from the desert zone contain substantially high relative abundance of Chenopodiaceae while those from the steppe zone are dominated by *** ratios show great potential in terms of separating different vegetation zones and to indicate climate changes on the Tibetan *** Artemisia/Chenopodiaceae ratio and arboreal/non-arboreal pollen ratio could be used as proxies for winter ***/Cyperaceae ratio and the sum of relative abundance of xerophilous elements increase with enhanced warming and *** considering the vegetation coverage around the lakes,hierarchical cluster analysis suggests that the studied sites can be divided into four clusters:meadow,steppe,desert-steppe,and *** pollen-based vegetation classification models are established using a random forest *** random forest model can effectively separate the modern pollen assemblages of the steppe zone from those of the desert zone on the Tibetan *** model for distinguishing the four vegetation clusters shows a weaker but still valid classifying *** is expected that the random forest model can provide a powerful tool to reconstruct the palaeovegetation succession on the Tibetan Plateau when more pollen data from surface lake sediments are included.

关键词： Modern pollen assemblage Tibetan Plateau Surface lake sediment Pollen-climate relationship Pollen-based vegetation classification model

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The battle of crops against drought:Genetic dissection and improvement

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Journal of Integrative Plant Biology 2023年第2期65卷 496-525页

作者： Zhirui Yang feng qin State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijing 100193China

With ongoing global climate change,water scarcity-induced drought stress remains a major threat to agricultural *** undergo a series of physiological and morphological changes to cope with drought stress,including stomatal closure to reduce transpiration and changes in root architecture to optimize water *** phenotypic and multi-omics studies have recently identified a number of drought-related genetic resources in different crop *** functional dissection of these genes using molecular techniques has enriched our understanding of drought responses in crops and has provided genetic targets for enhancing resistance to ***,we review recent advances in the cloning and functional analysis of drought resistance genes and the development of technologies to mitigate the threat of drought to crop production.

关键词： crops drought resistance gene cloning genetic improvement

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Understanding the pathogenic evolution of Zika virus

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Science China(Life Sciences) 2016年第7期59卷 737-739页

作者： Xiao-feng qin Center of Systems Medicine Institute of Basic Medical Sciences Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100005 China Suzhou Institute of Systems Medicine Suzhou 215123 China

Unlike the previous circulating strains that were not associ- ated with significant human pathology, recent circulating Zika virus （ZIKV） strains isolated during the 2015-2016 Brazilian Outbreak are highly suspected to cause neuropa- thology, including disorders of fetal brain development and Guillain-Barr6 syndrome （Broutet et al., 2016）. Studies have revealed that recent ZIKV strains can be spread through maternal-fetal （Calvet et al., 2016） and sexual （Hills et al., 2016） transmission, in addition to the traditional route of infection via mosquitoes.

关键词：病毒演变病原大脑发育病理学流行株综合征菌株

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Biome reconstruction on the Tibetan Plateau since the Last Glacial Maximum using a machine learning method

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Science China Earth Sciences 2022年第3期65卷 518-535页

作者： feng qin Yan ZHAO Xianyong CAO Key Laboratory ofLand Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Alpine Paleoecology and Human Adaptation(ALPHA)Group State Key Laboratory of Tibetan Plateau Earth System Science(LATPES)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Historical biome changes on the Tibetan Plateau provide important information that improves our understanding of the alpine vegetation responses to climate ***,a comprehensively quantitative reconstruction of the historical Tibetan Plateau biomes is not possible due to the lack of quantitative methods that enable appropriate classification of alpine biomes based on proxy data such as fossil pollen *** this study,a pollen-based biome classification model was developed by applying a random forest algorithm(a supervised machine learning method)based on modern pollen assemblages on and around the Tibetan Plateau,and its robustness was assessed by comparing its results with the predictions of the biomisation *** results indicated that modern biome distributions reconstructed using the random forest model based on modern pollen data generally concurred with the observed zonal *** random forest model had a significantly higher accuracy than the biomisation method,indicating the former is a more suitable tool for reconstructing alpine biome changes on the Tibetan *** random forest model was then applied to reconstruct the Tibetan Plateau biome changes from 22 ka BP to the present based on 51 fossil pollen *** reconstructed biome distribution changes on the Tibetan Plateau generally corresponded to global climate changes and Asian monsoon *** the Last Glacial Maximum,the Tibetan Plateau was mainly desert with subtropical forests distributed in the *** the last deglaciation,the alpine steppe began expanding and gradually became zonal vegetation in the central and eastern *** meadow occupied the eastern and southeastern areas of the Tibetan Plateau since the early Holocene,and the forest-meadow-steppe-desert pattern running southeast to northwest on the Tibetan Plateau was established *** the mid-Holocene,subtropical forests extended north,which reflected the“optimum”***

关键词： Biome reconstruction Random forest algorithm Biomisation method Pollen data Last Glacial Maximum Tibetan Plateau

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Future Digital Design and Manufacturing: Embracing Industry 4.0 and Beyond

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1047-1049页

作者： Sheng-feng qin Kai Cheng School of Design Northumbria University College of Engineering Design and Physical SciencesBrunel University London

Digital design and manufacturing have been around for several decades from the numerical control of machine tools and automating engineering design in 1960s, through early Computer Aided Design （CAD）/Computer Aided Engineering analysis （CAE）/Computer Aided Manufacturing （CAM）, to modem digital design and manufacturing [1], and cloud manufacturing [2] converging into product lifecycle management （PLM） [3, 4] and Internet-enabled personalized manufacturing [5].

关键词： Digital design Future manufacturing Industry 4.0

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Chemical constituents and biological activities of lycophytes and ferns

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Chinese Journal of Natural Medicines 2019年第12期17卷 887-891页

作者： ZHU qin-feng ZHAO qin-Shi State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences

Lycophytes and ferns are unique and charismatic members of many terrestrial ecosystems and occupy the pivotal position in land plant origin and *** Chinese lycophytes and ferns flora,with approximately 2000 species,contributes a substantial component to the global lycophytes and ferns diversity,with estimates of 12000 *** them,about 433 species are medicinally recorded and researches based on their phytochemical properties are important topics in natural *** paper reviewed the research history and current status of chemical constituents and biological activities of lycophytes and ferns,which had highlighted the research progress of our group.

关键词： Lycophytes Ferns Chemical constituents Biological activities Lycopodium alkaloids

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Fault Diagnosis Model Based on Feature Compression with Orthogonal Locality Preserving Projection

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Chinese Journal of Mechanical Engineering 2011年第5期24卷 891-898页

作者： TANG Baoping LI feng qin Yi State Key Laboratory of Mechanical Transmission Chongqing University Chongqing 400030 China

Based on feature compression with orthogonal locality preserving projection（OLPP）,a novel fault diagnosis model is proposed in this paper to achieve automation and high-precision of fault diagnosis of rotating *** this model,the original vibration signals of training and test samples are first decomposed through the empirical mode decomposition（EMD）,and Shannon entropy is constructed to achieve high-dimensional *** order to replace the traditional feature extraction way which does the selection manually,OLPP is introduced to automatically compress the high-dimensional eigenvectors of training and test samples into the low-dimensional eigenvectors which have better *** that,the low-dimensional eigenvectors of training samples are input into Morlet wavelet support vector machine（MWSVM） and a trained MWSVM is ***,the low-dimensional eigenvectors of test samples are input into the trained MWSVM to carry out fault *** evaluate our proposed model,the experiment of fault diagnosis of deep groove ball bearings is made,and the experiment results indicate that the recognition accuracy rate of the proposed diagnosis model for outer race crack、inner race crack and ball crack is more than 90%.Compared to the existing approaches,the proposed diagnosis model combines the strengths of EMD in fault feature extraction,OLPP in feature compression and MWSVM in pattern recognition,and realizes the automation and high-precision of fault diagnosis.

关键词： orthogonal locality preserving projection(OLPP) manifold learning feature compression Morlet wavelet support vector machine(MWSVM) empirical mode decomposition(EMD) fault diagnosis

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Dynamic Behavior and Function of Foxp3^+ Regulatory T Cells in Tumor Bearing Host

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Cellular & Molecular Immunology 2009年第1期6卷 3-13页

作者： F. Xiao-feng qin Department of Immunology The University of TexasMD Anderson Cancer Center The University of Texas Graduate School of Biomedical Sciences at Houston

Regulatory T cells （Tregs） expressing forkhead/winged-helix transcription factor Foxp3 represent a distinct lineage of lymphocytes which play a central role in protecting the host from autoimmune diseases. However, Tregs also pose a major problem to anti-tumor immunity. Growing body of evidence from both laboratory and clinical investigations has demonstrated that expansion and accumulation of these immunosuppressive cells correlates with advanced tumor growth and predicts poor disease prognosis. How tumor development subverts normal self-tolerance function of Tregs thereby thwarts host anti-tumor immunity remains elusive. This review will discuss our current knowledge in understanding the dynamics and plasticity of Foxp3~ Treg activation and induction in tumor bearing hosts and their interaction with various antigen presenting cells （APCs） in tumor microenvironment leading to the establishment of active local and systemic immune suppression. Cellular ＆ Molecular Immunology.

关键词： Treg APC tumor microenvironment immune suppression anti-tumor immunity

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Quasiprobability Distribution of Squeezed Thermal Spin States in Ferromagnet

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Communications in Theoretical Physics 2008年第3期49卷 777-782页

作者： XU qin-feng CHENG Ze Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We study squeezed properties of magnon squeezed thermal spin states by using the distribution of Q function in the ferromagnet. It is found that the distribution of Q function strongly depends on the temperature T and coupling parameter γ. Below the transition temperature Tc, the distribution Q function in the squeezed thermal spin state presents a richer structure than in the normal state. Non-classical effects have been observed. In the transition from the normal to the squeezed thermal spin state, the phase symmetry of the magnon system is spontaneously broken.

关键词： squeezed thermal spin state ferromagnon quasiprobability distribution function

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Genetic dissection of drought resistance for trait improvement in crops

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The Crop Journal 2023年第4期11卷 975-985页

作者： Shengxue Liu Hongwei Wang feng qin College of Biological Sciences China Agricultural UniversityBeijing 100193China Agricultural College Yangtze UniversityJingzhou 434025HubeiChina

Reliance on agriculture for food security is a constant in all modern *** climate change and population growth have put immense pressure on sustainable agriculture,exacerbating the effects of environmental *** is one of the most pressing abiotic stresses that farmers face,presenting an annual threat to crop growth and *** have evolved extensive morphological,physiological,and molecular mechanisms to combat drought *** resistance is a polygenic trait,controlled by a complex genetic network and an array of genes working together to ensure plant *** studies have aimed at dissecting the genetic mechanisms underlying drought *** studies using linkage and association mapping have made progress in identifying genetic variations that affect drought-resistance *** loci may potentially be engineered by genetic transformation and genome editing aimed at developing new,stress-resistant crop *** we summarize recent progress in elucidating the genetic basis of crop drought ***-breeding technologies such as marker-assisted selection,genome selection,gene transformation,and genome editing are currently employed to develop drought-resistant germplasm in a variety of *** advances in basic research and crop biotechnology covered in this review will facilitate delivery of drought-resistant crops with unprecedented efficiency.

关键词： Drought resistance QTL GWAS Molecular breeding

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